Abaixo está uma instrução que descreve uma tarefa de geração de SQL, combinada com uma entrada que fornece mais contexto sobre os esquemas de tabela disponíveis. Escreva o código SQL que responda adequadamente à solicitação
 ###Instrução: Qual é o total de anos com uma Posição de 12º lugar?
 ###Tabelas: CREATE TABLE series_ratings (series_ratings_id AUTO_INCREMENT PRIMARY KEY, Season INT, # of Episodes INT, Timeslot VARCHAR, Season Premiere VARCHAR, Season Final VARCHAR, Peak Audience INT, Average Audience INT, Average Nightly Rank VARCHAR, Average Weekly Rank VARCHAR, Average Yearly Ranking VARCHAR) CREATE TABLE membership (membership_id AUTO_INCREMENT PRIMARY KEY, School VARCHAR, City VARCHAR, Team Name VARCHAR, Enrollment 08-09 INT, IHSAA Class VARCHAR, IHSAA Class Football VARCHAR, County VARCHAR, Year Joined (Or Joining) INT, Previous Conference VARCHAR) CREATE TABLE achievements (achievements_id AUTO_INCREMENT PRIMARY KEY, Year INT, Competition VARCHAR, Venue VARCHAR, Position VARCHAR, Event VARCHAR, Notes VARCHAR) CREATE TABLE barangays_districts (barangays_districts_id AUTO_INCREMENT PRIMARY KEY, Barangay VARCHAR, District VARCHAR, Population (May 1, 2000) INT, Population (August 1, 2007) INT, Population (May 1, 2010) VARCHAR) CREATE TABLE composition (composition_id AUTO_INCREMENT PRIMARY KEY, Company VARCHAR, ICB Sector VARCHAR, Ticker symbol VARCHAR, Index weighting (%) at 17 January 2013 VARCHAR, Market cap. at April 2013 (€) VARCHAR)  
SELECT SUM Year FROM achievements WHERE Position = 12th